This invention relates to a space heating system, and more particularly to an outdoor furnace connected to a building for heating a space within the building.
Furnaces of various types are well known in the art. Some outdoor furnaces are also known, such as those illustrated in the following U.S. Pat. Nos.:
______________________________________ 184,201 Trench Nov. 7, 1876 4,138,985 Marley Feb. 13, 1979 4,194,688 Cobos March 25, 1980 ______________________________________
However, in each of the above patents, although the furnace is located outside of the structure to be heated, the only connection between the furnace and the heated structure is the hot air duct conducting heated air from the furnace into a space within the structure. However, the air to be heated is drawn into the furnace from the atmosphere, and therefore a complete circulation of conditioned air between the heated structure and the furnace is absent in each of the above three patents.
The Trench patent discloses a spiral flue around the combustion fuel chamber and the Marley patent discloses a baffle plate in the upper portion of a combustion chamber, for extending the heating path of the air. Nevertheless, none of the above patents disclose an outdoor furnace having the heat exchange structures which characterize the furnace made in accordance with this invention.
Other types of prior art furnaces are disclosed in the following U.S. Pat. Nos.:
______________________________________ 2,355,495 Zier, Jr. Aug. 8, 1944 2,703,567 Manchester et al March 8, 1955 2,879,762 Robson March 31, 1959 3,889,653 Scogin June 17, 1975 4,003,362 Lener Jan. 18, 1977 4,004,731 Zung Jan. 25, 1977 ______________________________________